Spacer for a warehouse rack-aisle heat transfer system

ABSTRACT

A spacer for use in stacking a plurality of cases containing a quantity of product on a pallet to form a pallet assembly and to facilitate heat transfer to or from the product is described. Installations for retaining a quantity of product at a desired temperature including a storage warehouse space including a rack-aisle heat transfer system incorporating pallet assemblies including spacers of the present disclosure are also described. The spacer of the present disclosure is useful to transfer heat to and from a quantity of warehouse product through both conduction and forced convection. The spacers provide an airflow path through at least one airflow channel between opposing sides of the pallet assembly so that airflow is not lost through sides adjacent to the opposing sides of the pallet assembly. The spacers further provide a consistent support surface for cases positioned above and below the spacers.

BACKGROUND

1. Technical Field

The present disclosure relates to a warehouse that is capable ofaltering and/or holding steady the temperature of a quantity of producthoused in cases forming pallet assemblies and storing such product,e.g., bulk foods. More particularly, the present disclosure relates tospacing, stacking and heat transfer structures used in such a warehouse.

2. Description of the Related Art

Two-stage freezer warehouses are known in which large pallets of itemsincluding meats, fruit, vegetables, prepared foods, and the like arefrozen in blast rooms of a warehouse and then are moved to a storagepart of the warehouse to be maintained at a frozen temperature untiltheir removal. Such two-stage freezer warehouses require separate blastand storage rooms that encompass a relatively large amount of space.

U.S. patent application Ser. No. 12/877,392 entitled “Rack-AisleFreezing System for Palletized Product”, filed on Sep. 8, 2010, theentire disclosure of which is hereby explicitly incorporated byreference herein, relates to an improved system for freezing foodproducts. Shown in FIG. 1 is a large warehouse 2 that can be used tofreeze and maintain perishable foods or like products. Large pallets ofitems, including meats, fruits, vegetables, prepared foods, and thelike, are sent to warehouse 2 to be frozen employing a system wherebythe palletized foods are frozen on storage racks.

FIG. 2 shows a top view of the interior of warehouse 2, in which rows ofpalletized product are shown such that pallet assemblies 52 a abutchamber 6. As shown in FIG. 3, rows of racking 14 (see also FIG. 8) arepositioned between aisles 10 and chambers 6. Each chamber 6 is enclosedby a pair of end walls 15 and top panel 17. Spacers 20 (FIGS. 5 and 6)separate rows of cases 22 to create a palletized product stack in theform of pallet assembly 52 a which can be disposed and sealed againstthe exterior of racking 14 (FIG. 3) via forklifts 18 (see, e.g., FIGS. 3and 4).

Air handlers 8, e.g., chillers (FIG. 2) provided in the interior ofwarehouse 2 produce conditioned, e.g., cold air and maintain thetemperature of ambient air within the warehouse space at a desiredtemperature, e.g., +55° F. to −30° F. While warehouse 2 could beutilized to either freeze or thaw a quantity of product housed in casescontained on pallet assemblies 52 a, the remaining description will usethe example of a warehouse freezer, it being understood that similararrangements and principles will be applied to a warehouse utilized tothaw product, with the air handler comprising a heater as opposed to achiller.

Adjacent pairs of racking structures 14 (FIGS. 2-4) define a pluralityof adjacent airflow chambers 6 (FIGS. 2 and 4) having air intakeopenings on opposite sides thereof and a plurality of air outlets havingair moving devices, such as exhaust fans 12, on top panels 17, whichcause freezing air to be drawn into chambers 6 through the air intakeopenings in racking 14 and to then exhaust into the warehouse space. Theplurality of airflow chambers 6 are each defined by a pair of end walls15 and top wall 17 having one or more air outlets and exhaust fansassociated therewith (FIG. 3). Pallet assemblies 52 a (FIG. 5) arepressed against the intake openings in racking 14 such that a seal isformed between the pallets and the intake openings via side peripheryseals, a bottom periphery seal, and a top periphery seal that isselectively adjustable via a vertically manually adjustable bracket towhich the top periphery seal attaches. The seals together define eachintake opening. Freezing air is drawn through air pathways 16 (FIGS. 2,4, and 5) within the palletized product in a direction towards chamber 6to thereby quickly freeze the product. As shown in FIG. 5, spacers 20may be placed between rows of cases 22 of product in an attempt toprovide air pathways 24 through which air flow can enter chamber 6.

U.S. patent application Ser. No. 13/074,098 entitled “Swing Seal for aRack-Aisle Freezing and Chilling System”, filed on Mar. 29, 2011, theentire disclosure of which is hereby explicitly incorporated byreference herein discloses a top periphery seal useable to seal anintake opening as described above and which automatically adjusts to theheight of pallet assembly 52 a as illustrated in FIG. 6. As illustratedin FIG. 6, pallet assembly 52 a (comprised of a plurality of cases 22stacked on spacers 20 and pallet 4) can be positioned along pallet guide56 and pressed against intake opening 54 such that a seal is formedbetween pallet assembly 52 a and intake opening 54 via side peripheryseals, a bottom periphery seal and an automatically adjustable topperiphery seal surrounding intake opening 54. With such a construction,chilling or freezing air is drawn through air pathways 16 formed throughpallet assembly 52 a, as illustrated in FIGS. 2, 4 and 5.

FIG. 5 illustrates predicate spacer 20 which is formed in an undulating“egg carton” configuration. As illustrated in FIG. 7, individual cases22 can crush under the weight of the product contained therein and theproduct contained in cases stacked directly above to cause overlap ofcases 22 with a spacer 20 and prohibit air flow between product cases 22positioned on opposite sides of the obstructed spacer 20. Undulatingspacers 20 are particularly susceptible to obstruction due to droopingor sagging cases 22 due to the inconsistent support structure caused bythe hill and valley configuration of such spacers. FIG. 7 illustratescase crushing and drooping at various sides and levels of palletassembly 52 a; however, this phenomenon is, in practice, moreprevalently seen with respect to the spacers 20 separating lower rows ofcases 22, as the bottom of pallet assembly 52 a contains the heaviestload of cases 22 stacked thereon.

In the above described installation, utilizing “egg carton” spacers 20,heat transfer from chilled ambient air in warehouse 2 to the productscontained in cases 22 is effected through forced convection which isfacilitated by the irregular shape of egg carton spacers 20 to allow airflow in all directions through pallet assembly 52 a. Alternative spacerssuch as wood slat spacers may also be utilized to separate cases 22 onpallet 4; however, spacers employed in warehouse installations utilizedto keep the quantity of product at a desired temperature through forcedconvection are designed to allow for air flow in all directions. Becauseair can flow in all directions through predicate spacers 20 describedabove, thorough cooling or thawing of a product may not be achieved, asair entering between adjacent rows of product cases may exit palletassembly 52 a before encountering all of the cases of the row inquestion. Further, crushing and/or drooping of cases 22 may restrictairflow, as described above.

Another mechanism of heat transfer, i.e., conduction, can also beutilized to transfer heat to or from product. Predicate spacers 20described above are made either of wood or plastic, which is notsufficiently thermally conductive to effect heat transfer viaconduction. Therefore, in installations utilizing such spacers, heattransfer is effected solely by the use of forced convection.

SUMMARY

The present disclosure relates to a spacer for use in stacking aplurality of cases containing a quantity of product on a pallet to forma pallet assembly and to facilitate heat transfer to or from theproduct. The present disclosure further relates to installations forretaining a quantity of product at a desired temperature including astorage warehouse space including a rack-aisle heat transfer systemincorporating pallet assemblies including spacers of the presentdisclosure. The spacer of the present disclosure is formed of a materialhaving a thermal conductivity of at least 3 W/m·K, at least 5 W/m·K, orat least 10 W/m·K and includes at least one airflow channel whichprovides an air flow path through at least one airflow channel betweenopposing sides of the pallet assembly so that air flow is not lostthrough sides connecting the air inlet and outlet of the spacer channelsof the pallet assembly.

The disclosure, in one form thereof, provides an installation formaintaining a quantity of product at a desired temperature. Theinstallation of this form of the present invention includes a pluralityof pallet assemblies, a storage warehouse space having a plurality ofracks sized for receiving the plurality of pallet assemblies arranged inrows and columns on the racks, the pallet assemblies loaded with aquantity of product to be maintained at a desired temperature, each ofthe plurality of racks positioned adjacent to an aisle, so that aforklift can access each of the plurality of pallet assemblies. Theinstallation further includes at least one air handler connected to thewarehouse space to condition an ambient air in the warehouse space, theat least one air handler having an output sufficient to maintain atemperature of the ambient air in the warehouse space at a desiredtemperature. At least one air flow chamber is in fluid communicationwith a plurality of air intake openings formed through each of theplurality of racks. At least one fan is in fluid communication with theat least one air flow chamber, the fan operable to create a circulationof the ambient air flowing through the plurality of air intake openingsinto the at least one air flow chamber and back to the warehouse space.Each of the plurality of pallet assemblies includes a pallet, aplurality of cases containing the quantity of product; and at least onespacer, each spacer comprising a substantially planar first surfaceextending in an x-y plane of the Cartesian coordinate system, the planarfirst surface formed of first surface material, the planar first surfacedefining a spacer outer perimeter of a size and shape about congruent tothe outer perimeter of the pallet; a substantially planar second surfaceformed of second surface material and a plurality of supports extendingbetween the first surface and the second surface along a trajectoryhaving a directional component along a z-axis of the Cartesiancoordinate system. Each of the supports of the plurality of supportsspace the first surface from the second surface, the first surface, thesecond surface and the supports defining at least one air flow channel,the at least one air flow channel spanning a pair of opposing sides ofthe at least one spacer so that one of the pair of opposing sides of thespacer comprises an air flow inlet and the other of the opposing sidescomprises an air flow outlet. As air flow enters the at least one airflow channel at the inlet traverses the channel and exits the channel atthe outlet to define an air filter trajectory from the inlet to theoutlet along an x-axis of the Cartesian coordinate system. The pluralityof supports substantially preclude the air flow from exiting the channelalong a trajectory defined by the y-axis of the Cartesian coordinatesystem. Each of the plurality of cases are stacked on a pallet of one ofthe plurality of pallet assemblies in a plurality of case layers whichare separated from each other by a plurality of the spacers.

BRIEF DESCRIPTION OF THE DRAWINGS

The above mentioned and other features and objects of this disclosure,and the manner of attaining them, will become more apparent and thedisclosure itself will be better understood by reference to thefollowing description of embodiments of the disclosure taken inconjunction with the accompanying drawings, wherein:

FIG. 1 is a perspective view of a warehouse incorporating a heattransfer system in accordance with the present disclosure;

FIG. 2 is a diagrammatic top view of a heat transfer warehouseincorporating the system of the present disclosure;

FIG. 3 is a perspective view of the interior of the warehouseillustrated in FIG. 1;

FIG. 4 is a perspective, end view of two rows of racking separated by anair flow chamber;

FIG. 5 is a perspective view showing a desired air flow through a palletassembly;

FIG. 6 is a perspective view illustrating loading of pallet assembliesinto the racking illustrated, e.g., in FIGS. 3 and 4;

FIG. 7 is a perspective view of a pallet assembly incorporating apredicate spacer;

FIG. 8 is a perspective view of a portion of a racking structureaccommodating 24 pallet assemblies on each side thereof;

FIG. 9 is an end view of a pallet assembly in accordance with thepresent disclosure;

FIG. 10 is a perspective view of a spacer in accordance with the presentdisclosure;

FIG. 11 is a perspective view of an alternative embodiment spacer inaccordance with the present disclosure;

FIG. 12 is a perspective view illustrating a stack of a plurality of thespacers illustrated in FIG. 10, with an automated suction lifting devicebeing utilized to remove and transport one of the spacers;

FIG. 13 is a perspective view of an alternative embodiment spacer inaccordance with the present disclosure;

FIG. 14 is a sectional view of the spacer of FIG. 13 taken along line14-14;

FIG. 15 is a partial, end view of the spacer illustrated in FIG. 10;

FIG. 16 is a partial, end view of an alternative embodiment spacer inaccordance with the present disclosure;

FIG. 17 is an end view of yet another alternative embodiment spacer inaccordance with the present disclosure;

FIG. 18 is a partial, end view of a further alternative embodimentspacer in accordance with the present disclosure; and

FIG. 19 is a partial perspective view of an additional alternativeembodiment spacer in accordance with the present disclosure.

Corresponding reference characters indicate corresponding partsthroughout the several views. Although the exemplifications set outherein illustrate embodiments of the disclosure, in several forms, theembodiments disclosed below are not intended to be exhaustive or to beconstrued as limiting the scope of the disclosure to the precise formsdisclosed.

DETAILED DESCRIPTION

Referring to FIG. 10, spacer 30 includes a substantially planar firstsurface 32 extending in an x-y plane of a Cartesian coordinate system.For the purposes of this document, “substantially planar” is meant todenote nominally planar. Similarly, spacer 30 includes substantiallyplanar second surface 34 opposite first surface 32 and extendinggenerally parallel to first surface 32. Substantially planar firstsurface 32 and substantially planar second surface 34 both present aconsistent support structure for abutting cases 22, as depicted in FIG.9. Because of the consistent support surface provided by substantiallyplanar first surface 32 and substantially planar second surface 34, thedrooping and blockage of air flow associated with egg carton spacer 20(see, e.g. FIGS. 5 and 7) is avoided.

Substantially planar first surface 32 and substantially planar secondsurface 34 are both formed from plates of material having a thermalconductivity of at least 3 W/m·K, at least 5 W/m·K, or at least 10 W/m·Kso that spacer 30 is operable to effect heat transfer with productcontained in cases 22 via conduction. Referring to FIG. 10, supports 36extend between first surface 32 and second surface 34 to define aplurality of air flow channels 38 spanning air flow inlet side 40 andair flow outlet side 42 of spacer 30. Air flow channels 38 may beoriented along either the length or the width of the spacer, dependingupon the warehouse installation being utilized. Supports 36 span theentire length of first surface 32 and second surface 34 and block airflow from exiting an air flow channel 38 along a trajectory defined bythe y-axis of the Cartesian coordinate system depicted in FIG. 10. Whenused with reference to a plane or axis of a Cartesian coordinate system,“along” is meant to denote a trajectory coextensive with such plane oraxis or parallel to such plane or axis. A plurality of spacers 30 can beutilized to create pallet assembly 52, as illustrated in FIG. 9. In thisconfiguration, pallet assembly 52 is usable in a temperature controlledwarehouse to either freeze or thaw a quantity of product housed in cases22 contained on pallet assemblies 52. With spacers 30, heat transfer toor from the product contained within cases 22 can be effected by bothconduction and forced conduction, as further described below. Palletassemblies 52 in accordance with the present disclosure can beassociated with warehouse assembly 2 in the same way as prior art palletassemblies 52 a described above.

Pallet assemblies 52 form a part of warehouse installation 2 depicted,e.g., in FIG. 2. The general structure and components of warehouse 2 aredescribed above in the background section of this document. A portion ofthis description will be repeated here to facilitate an understanding ofthe present invention. As illustrated in FIG. 2, warehouse 2 includesrack rows 26 separated by chambers 6 and aisles 10. As illustrated inFIGS. 3 and 4, racks 14 are sized for receiving a plurality of palletassemblies 52. As depicted, e.g., in FIG. 9, pallet assemblies 52include pallet 4, on which a plurality of cases 22 are stacked, withspacers 30 interposed between layers of cases 22. Racking 14 can besized to receive a different number of pallet assemblies, as necessary.Different assemblies of racking 14 are illustrated, e.g., in FIGS. 3, 4and 8.

With pallet assemblies 52 arranged in rows and columns on racks 14,warehouse installation 2 can be utilized to maintain the quantity ofproduct contained in cases 22 at a desired temperature. As illustratedin FIGS. 3 and 4, aisles 10 are sufficiently wide to allow forklifts 18to access pallet assemblies 52. Typical aisle width is between 5 foot to14 foot depending on the type of lift equipment. Pallet assemblies 52each include a pallet 4 at the bottom thereof. As used in this document,“pallet” is used to denote a standard warehouse pallet of box sectionopen at at least two ends (some pallets are called 4-way pallets due tofork openings on all 4-sides) to allow the entry of the forks of aforklift so that a palletized load, i.e., pallet assembly 52, can beraised and moved about easily.

As described above, racks 14 define air intake openings fluidlyconnected to a chamber 6, which, in the exemplary embodiment illustratedis enclosed by a pair of end walls 15 and top panel 17. Palletassemblies 52 are disposed and sealed against the air intake openingsformed in racks 14. Referring to FIG. 2, air handlers 8 are operablyconnected to warehouse space 2 so that air handlers 8 can condition theambient air in warehouse space to a desired temperature. In the eventthat warehouse space 2 is utilized to freeze product contained in cases22, air handlers 8 may produce air on the order of −5° F. to −30° F. Inthe event that warehouse space 2 is utilized to thaw product containedin cases 22, air handlers 8 may produce air on the order of 30° F. to60° F. Fans 12 circulate ambient air conditioned by air handlers 8 suchthat air conditioned by air handlers 8 flows through pallet assemblies52 and thereafter through the air intake openings formed in racks 14.

As mentioned above, each pallet assembly 52 includes a plurality ofcases 22 stacked atop a pallet 4, with spacers 30 separating each layerof cases 22. Referring to FIG. 10, each spacer 30 includes substantiallyplanar first surface 32 and substantially planar second surface 34, witha plurality of supports 36 extending between first surface 32 and secondsurface 34 along a trajectory defined by the z-axis of the Cartesiancoordinate system illustrated in FIG. 10. Stated another way, firstsurface 32 is separated from second surface 34 along the z-axis bysupports 36. First surface 32 and second surface 34 extend in the x-yplane of the Cartesian coordinate system illustrated in FIG. 10.

Each of first surface 32 and second surface 34 are sized and shaped tobe about congruent to the outer perimeter of pallet 4. In one exemplaryembodiment, pallet 4 comprises a standard 40 inch by 48 inch rectangularouter perimeter. With such a pallet, first surface 32 and second surface34 will both be substantially rectangular in shape and about 40 inchesby about 48 inches. Stated another way, first surface 32 and secondsurface 34 are both nominally rectangular and nominally measure about 40inches by 48 inches. In certain alternative embodiments, spacers 30 willbe slightly oversized with respect to pallet 4, e.g., by having anoverhang of up to an inch relative to the perimeter of pallet 4. Theseembodiments are also considered to be sized and shaped “about congruent”to the outer perimeter of pallet 4. Alternative pallet sizes, such as astandard European pallet may be utilized. Spacers 30 will be aboutcongruent to whatever pallet they are designed for use with.

In certain embodiments, spacers 30 will be oversized along the z-axis ofthe Cartesian coordinate system depicted in FIG. 10. For example, spacer30 may include a dimension of about 41 inches along the z-axis ascompared to a corresponding dimension of pallet 4 of 40 inches. Becausecases 22 are sized to be positioned into configurations corresponding tothe standard 40 inch by 48 inch pallet, a spacer sized at 41 inchesalong the x-axis can provide for an overlap of one inch with respect toa row of cases at either airflow inlet side 40 or airflow outlet side42. A spacer 30 measuring 41 inches along the x-axis may also beutilized to provide an overlap of one-half inch at both airflow inletside 40 and airflow outlet side 42. In an alternative embodiment, spacer30 measures 42 inches along the x-axis to provide for additionaloverlap. In this embodiment, the consistent surfaces provided bysubstantially planar first surface 32 and substantially planar secondsurface 34 together with the overlap along the x-axis cooperate toprevent drooping or sagging of cases 42 which would block airflowthrough channels 38, which is further described hereinbelow.

Supports 36 extend along the x-axis of the Cartesian coordinate systemdepicted in FIG. 10. Supports 36 cooperate with the opposing platesforming substantially planar first surface 32 and substantially planarsecond surface 34 to form air flow channels 38 spanning opposing sidesof spacer 30. Specifically, air flow channels 38 span air inlet side 40and air outlet side 42. Channels 38 allow a flow of conditioned aircreated by air handlers 8 and circulated by fans 12 to enter air flowinlet side 40 of channels 38, traverse channels 38 and exit through airflow outlet side 42 of spacer 30. In the exemplary embodimentillustrated in FIGS. 9, 10 and 12, supports 36 are formed of extrudedaluminum box tubes. In an exemplary embodiment, the extruded aluminumbox tubes forming supports 36 are formed of 14 gauge aluminum forming atube having a square outer perimeter and a square inner perimeterdefining a longitudinal channel extending the length of support 36.

Each support 36 is secured to an aluminum plate defining first surface32 and a second aluminum plate defining second surface 34. In anexemplary embodiment, the opposing aluminum plates are formed of 14gauge aluminum. When formed of aluminum, spacer 30 may have a thermalconductivity of at least 10 W/m·K. Supports 36 may be secured to theopposing plates using a variety of techniques including welding.Alternative materials of construction may be utilized to form spacers30, including various metals and polymers such as high densitypolyethylene or polycarbonate may be utilized. If polymeric material isutilized to form spacers 30, then they can have a thermal conductivityof at least 3 W/m·K or at least 5 W/m·K.

Air flow channels 38 defined by supports 36 and the opposing plates onwhich first surface 32 and second surface 34 of spacer 30 are formedprovide air flow generally along the x-axis of the Cartesian coordinatesystem depicted in FIG. 10. When air flow traverses air flow channels 38from air flow inlet side 40 to air flow outlet side 42, the flow withinchannels 38 may at times be turbulent, such that the air flow has vectorcomponents along the y- and z-axes of the Cartesian coordinate systemdepicted in FIG. 10; however, the gross air flow remains along thex-axis. That is, securement of supports 36 to the opposing platesdefining first surface 32 and second surface 34 substantially precludethe air flow from exiting air flow channels 38 along a trajectorydefined by the y-axis. While minor discontinuities in the securement ofsupports 36 to the plates forming first surface 32 and second surface 34may allow a very minor bit of airflow leakage along the y-axis, suchlosses will be small. Air losses from air flow channels 38 will ideallybe nonexistent. In certain exemplary embodiments, accounting formanufacturing processes, air flow loss from air flow channels 38 along atrajectory defined by the y-axis could be approximately 2% or maybe evenas high as 5%. In these instances, supports 36 will still be said tosubstantially preclude air flow from exiting air flow channels 38 alonga trajectory defined by the y-axis of the Cartesian coordinate system.Similarly, the opposing plates on which first surface 32 and secondsurface 34 are formed preclude air flow from exiting air flow channels38 along the z-axis. This structure therefore provides for no loss ofheat transfer by the escape of air flow through the sides of spacer 30spanning air flow inlet side 40 and air flow outlet side 42, whichenhances the efficiency of heat transfer in an installation arranged inaccordance with the present disclosure.

Generally speaking, the top plate and bottom plate of spacers 30 fromwhich substantially planar first surface 32 and substantially planarsecond surface 34 are defined, are formed of a material having a thermalconductivity of at least 3 W/m·K (watts per meter kelvin), at least 5W/m·K, or at least 10 W/m·K. Therefore, heat transfer between spacers 30and the product contained in cases 22 will occur via conduction as wellas forced convection (with the circulating air flow of warehouse 2contacting cases 22 between spacers 30). Because of the consistentsurface provided by substantially planar first surface and substantiallyplanar second surface, cases 22 will be well supported above spacers 30and will not be able to sag to obscure air flow through air flowchannels 38. Further, this consistent surface will provide excellentconduction of heat energy between the product contained within cases 22and spacers 30. Generally, a metal will be used to form the top plateand bottom plate of spacers 30. To avoid the potential of cases 22sticking to first surface 32 and second surface 34, the plates formingthese surface may be coated with a non-stick material such aspolytetrafluorethylene (PTFE), such as Teflon® sold by DuPont. In analternative configuration a single use non-stick coating of, e.g.,vegetable oil may be applied to substantially planar first surface 32and substantially planar second surface 34.

In certain embodiments of the present disclosure, substantially planarfirst surface 32 and substantially planar second surface 34 includeperforations 44, as illustrated in FIG. 11. In such an embodiment, heattransfer between spacers 30 and the product contained in cases 22 viaforced convection will be increased, as air flow through air channels 38will traverse perforations 44 and thereafter encounter cases 22.Further, using a perforated plate to define first surface 32 and secondsurface 34 of spacer 30 decreases the cost of spacer 30. In certainembodiments, perforations 44 will be limited to an individual size thatis small enough to prevent droop of cases 22 into perforations 44. Incertain embodiments of the present disclosure, perforations 44 couldaccount for removal of 90% of the material of the upper or lower platein question that would otherwise (i.e., in the absence of theperforations) be encompassed by the outer perimeter of spacer 30.

In an embodiment employing perforations 44, suction gripping surfaces 46defining continuous surfaces free of perforations 44 sized to receive asuction gripping device, as illustrated, e.g., in FIG. 12 may beprovided. In certain embodiments, suction gripping surfaces 46 may besized to receive a suction cup having an outer diameter of 2 inches. Toaccommodate this size suction cup, the continuous surfaces free ofperforations 44 may include any polygonal structure large enough tocontain a 2 inch circle. Therefore, the area of such surfaces free ofperforations 44 will be at least 3.2 inches and will likely be foursquare inches (a two inch by two inch square) or higher.

As described above, spacer 30 may be formed of a 14 gauge aluminum.Spacer 30 may also be formed of a 304 stainless steel material in a 14gauge or smaller size. Mild steels may also be utilized to form spacers30. In the embodiment illustrated in FIGS. 9, 10, 12 and 15, supports 36are spaced from each other by about 4 to 6 inches measured along thex-axis of the Cartesian coordinate system illustrated, e.g., in FIGS. 10and 11. Further, supports can be approximately 0.25 to 3 inches high asmeasured along the z-axis of the Cartesian coordinate systemillustrated, e.g. in FIG. 10. In embodiments in which supports 36comprise open ended tubing, such as the box tubing illustrated in FIGS.10, 12, and 13-15, supports 36 comprise further airflow channels throughtheir length because of their open ended tubular nature.

In the alternative embodiment illustrated in FIGS. 13 and 14, spacer 30incorporates lip 48 extending upwardly from substantially planar firstsurface 32 and surrounding the perimeter of first surface 32 to hold anypurge or liquid that is lost, e.g., when spacers 30 are used to thaw theproduct contained within cases 22. Spacers 30 of the present disclosuremay define load capacities of, e.g., 1800 or 3600 pounds.

FIGS. 16-18 illustrate alternative spacers 30 a, 30 b, and 30 cutilizing different supports 36A, 36B and 36C or some combinationthereof. As illustrated in FIG. 16, supports 36A extend at an angle inthe y-z plane and define triangularly shaped air flow channels 38Atherebetween. The configuration illustrated in FIG. 17 includesvertically positioned supports 36B which extend along the z-axis tocreate air flow channels 38B. Vertically extending supports 36B may alsobe utilized at the ends of spacer 30A as illustrated in FIG. 16.Supports 36A and 36B may be secured in place by, e.g., welding and maybe formed of the same material, including the same gauge of material asthe plates forming substantially planar first surface 32 andsubstantially planar second surface 34 of spacer 30. FIG. 18 illustratesa further alternative embodiment incorporating supports 36C in the formof integral ends of open ended rectangular channel pieces 50, which mayeach be monolithically formed as a single unitary structure. Asillustrated in FIG. 18, open ended rectangular channels 50 which defineair flow channels 38C therethrough can be secured to one another byforming an aperture through adjacent supports 36C and securing adjacentopen ended rectangular channels 50 to one another by inserting a bolttherethrough and fastening a nut in place as illustrated in FIG. 18. Anyof the supports 36 contemplated by the present disclosure can have aheight along the z-axis of about 0.25 to 3 inches. With respect tosupports such as supports 36 a which extend at an angle in the y-zplane, the height of such support is defined as the length it travelsfrom one end to the other along the z-axis.

FIG. 19 illustrates another exemplary spacer 30 d. Spacer 30 d includesa single airflow channel 38 d extending between airflow inlet side 40 dand airflow outlet side 42 d. Specifically, airflow channel 38 d isformed between supports 36 d, which are formed at the edges of theplates defining substantially planar first surface 32 d andsubstantially planar second surface 34 d that span airflow inlet side 40d and airflow outlet side 42 d. Stated another way, supports 36 arealigned along the x-axis of the Cartesian coordinate system illustratedin FIG. 19 and are secured to both of the plates forming substantiallyplanar first surface 32 d and substantially planar second surface 34 dalong their entire length along the x-axis at their extremities alongthe y-axis. Supports 36 d are the only supports of spacer 30 d that spanthe entire x-axis length of the plates forming substantially planarfirst surface 32 d and substantially planar second surface 34 d. Theremaining supports 36 d′ run less than the entire x-axis length of theupper and lower plates and provide mechanical support for the opposingplates, but do not define airflow channels from airflow inlet side 40 dto airflow outlet side 42 d. Supports 36 d′ are shown being orientedparallel to the x-axis; however, supports 36 d′ could be positioned inany desired orientation to provide mechanical support for the opposingplates. Supports 36 d are sufficient to eliminate airflow from exitingthe sides of spacer 30 d spanning airflow inlet side 40 d and airflowoutlet side 42 d. Any of the various supports of the present inventionmay be utilized in an embodiment similar to the one presented in FIG.19. Specifically, any of the supports may replace box tube support 36 drunning the entire length of the sides of spacer 30 d and any of thesupports may be truncated to provide mechanical support at desiredlocations and orientations throughout the body of a spacer.

Various exemplary spacers of the present invention and theircorresponding parts are denoted with primed reference numerals and/orreference numerals including an alphabetic designator such that similarparts of the various embodiments of spacer 30 include the same numericreference. Any of the features described with respect to any of thevarious embodiments of spacer 30 described above may be utilized inconjunction with any other feature of any of the alternative embodimentspacers described in the present application.

While this disclosure has been described as having an exemplary design,the present invention can be further modified within the spirit andscope of this disclosure. This application is therefore intended tocover any variations, uses, or adaptations of the disclosure using itsgeneral principles. Further, this application is intended to cover suchdepartures from the present disclosure as come within known or customarypractice in the art to which this disclosure pertains and which fallwithin the limits of the appended claims.

What is claimed is:
 1. An installation for maintaining a quantity ofproduct at a desired temperature, comprising: a plurality of palletassemblies; a storage warehouse space having a plurality of racks sizedfor receiving the plurality of pallet assemblies arranged in rows andcolumns on racks, the pallets assemblies loaded with a quantity ofproduct to be maintained at the desired temperature, each of saidplurality of racks positioned adjacent to an aisle, whereby a forkliftcan access each of the plurality of pallets assemblies; at least one airhandler operably connected to said warehouse space to condition anambient air in said warehouse space, said at least one air handlerhaving an output sufficient to maintain a temperature of the ambient airin said warehouse space at a desired temperature; at least one air flowchamber in fluid communication with a plurality of air intake openingsformed through each of said plurality of racks; at least one fan influid communication with said at least one air flow chamber, said fanoperable to create a circulation of the ambient air flowing through saidplurality of air intake openings, into said at least one air flowchamber and back to said warehouse space; at least one of said pluralityof pallet assemblies comprising: a pallet; a plurality of casescontaining the quantity of product; and at least one spacer, each saidspacer comprising: a substantially planar first surface extending in anx-y plane of a Cartesian coordinate system, said planar first surfaceformed of a first surface material, said planar first surface defining aspacer outer perimeter of a size and shape about congruent to the outerperimeter of the pallet; a substantially planar second surface formed ofa second surface material; and a plurality of supports extending betweensaid first surface and said second surface along a trajectory having adirectional component along a z-axis of the Cartesian coordinate system,whereby each of said plurality of supports space said first surface fromsaid second surface, said first surface, said second surface and saidsupports defining at least one airflow channel, said at least oneairflow channel spanning a pair of opposing sides of said at least onespacer, wherein one of said pair of opposing sides of said at least onespacer comprises an airflow inlet and the other of said pair of opposingsides of said at least one spacer comprises an airflow outlet, wherebyan airflow enters said at least one airflow channel at said airflowinlet, traverses said channel and exits said channel at said airflowoutlet to define an airflow trajectory from said inlet to said outletalong an x-axis of the Cartesian coordinate system, whereby saidplurality of supports substantially preclude the airflow from exitingsaid channel along a trajectory defined by the y-axis of the Cartesiancoordinate system; each of said plurality of cases stacked on saidpallet of one of said plurality of pallet assemblies in a plurality ofcase layers, each of said plurality of case layers separated fromanother of said plurality of case layers by one of a plurality of saidspacers; and said at least one of said plurality of pallet assembliesreceived on one of said plurality of racks and associated with one ofsaid plurality of air intake openings, whereby said circulation createdby said at least one fan causes the airflow through the channel in theat least one spacer.
 2. The installation of claim 1, wherein said atleast one airflow channel comprises a plurality of airflow channels. 3.The installation of claim 1, wherein said first surface and said secondsurface are both coated with polytetrafluorethylene.
 4. The installationof claim 1, wherein said first surface material forming saidsubstantially planar first surface of said at least one spacer has athermal conductivity of at least 3 W/m·K, and wherein said secondsurface material forming said substantially planar second surface ofsaid at least one spacer has a thermal conductivity of at least 3 W/m·K.5. The installation of claim 1, wherein said first surface materialforming said substantially planar first surface of said at least onespacer has a thermal conductivity of at least 5 W/m·K, and wherein saidsecond surface material forming said substantially planar second surfaceof said at least one spacer has a thermal conductivity of at least 5W/m·K.
 6. The installation of claim 1, wherein said first surfacematerial forming said substantially planar first surface of said atleast one spacer has a thermal conductivity of at least 10 W/m·K, andwherein said second surface material forming said substantially planarsecond surface of said at least one spacer has a thermal conductivity ofat least 10 W/m·K.
 7. The installation of claim 1, wherein said at leastone air handler comprises a chiller operable to maintain the temperatureof the ambient air in said warehouse space at the desired temperature of−5° F. to −30° F.
 8. The installation of claim 1, wherein said spacerouter perimeter substantially defines a rectangle measuring about 40inches by about 48 inches.
 9. The installation of claim 1, wherein saidspacer outer perimeter substantially defines a rectangle measuring about42 inches by about 48 inches.
 10. The installation of claim 1, whereinsaid spacer outer perimeter substantially defines a rectangle measuringabout 41 inches by about 48 inches.
 11. The installation of claim 1,wherein said spacer defines a load capacity for the quantity of productof about 1800 pounds.
 12. The installation of claim 1, wherein saidspacer defines a load capacity for the quantity of product of about 3600pounds.
 13. The installation of claim 1, wherein said first surfaceincludes a plurality of perforations, said perforations are arrangedsuch that at least one area of continuous surface free of saidperforations and sized to receive a suction gripping device is providedon said first surface, said at least one area of continuous surface freeof said perforations and sized to receive the suction gripping devicecomprising an area of 4 sq. in.
 14. The installation of claim 1, whereinsaid first surface and said second surface are both formed of analuminum material.
 15. The installation of claim 1, wherein said firstsurface and said second surface are both formed of a polycarbonatematerial.
 16. The installation of claim 1, wherein said first surfacecomprises a first surface of a first 14 gauge aluminum plate and saidsecond surface comprises a first surface of a second 14 gauge aluminumplate.
 17. The installation of claim 1, wherein said first surface andsaid second surface are both formed of a 304 stainless steel material.18. The installation of claim 1, wherein said first surface and saidsecond surface are both formed of a mild steel.
 19. The installation ofclaim 1, wherein said first surface and said second surface are bothformed of a polymer.
 20. The installation of claim 1, wherein saidsupports are spaced from each other by about 4-6 inches measured alongthe y-axis of the Cartesian coordinate system, and wherein said supportsextend along a trajectory defined by the z-axis to a height of about0.25 to 3 inches.
 21. The installation of claim 1, wherein said spacerfurther comprises a lip extending from said spacer outer perimeter. 22.The spacer of claim 1, wherein said first surface and said secondsurface are both coated with polytetrafluorethylene.
 23. A spacer forsupporting a plurality of cases on a pallet, each of said plurality ofcases containing a quantity of product to be maintained at a desiredtemperature, the spacer comprising: a substantially planar first surfaceextending in an x-y plane of a Cartesian coordinate system, said planarfirst surface formed of a first surface material, said planar firstsurface defining a spacer outer perimeter of a size and a shape aboutcongruent to the outer perimeter of the pallet; a substantially planarsecond surface formed of a second surface material; and a plurality ofsupports extending between said first surface and said second surfacealong a trajectory having a directional component along a z-axis of theCartesian coordinate system, each of said plurality of supports spacingsaid first surface from said second surface, said first surface, saidsecond surface and said supports defining at least one airflow channel,said at least one airflow channel spanning a pair of opposing sides ofsaid spacer, wherein one of said pair of opposing sides of said spacercomprises an airflow inlet and the other of said pair of opposing sidesof said spacer comprises an airflow outlet, whereby an airflow enterssaid at least one airflow channel at said airflow inlet, traverses saidchannel and exits said channel at said airflow outlet to define anairflow trajectory from said inlet to said outlet along an x-axis of theCartesian coordinate system, whereby said supports substantiallypreclude the airflow from exiting said channel along a trajectorydefined by the y-axis of the Cartesian coordinate system.
 24. The spacerof claim 23, wherein said at least one airflow channel comprises aplurality of airflow channels.
 25. The spacer of claim 22, wherein saidfirst surface material forming said substantially planar first surfaceof the spacer has a thermal conductivity of at least 3 W/m·K, andwherein said second surface material forming said substantially planarsecond surface of the spacer has a thermal conductivity of at least 3W/m·K.
 26. The spacer of claim 22, wherein said first surface materialforming said substantially planar first surface of the spacer has athermal conductivity of at least 5 W/m·K, and wherein said secondsurface material forming said substantially planar second surface of thespacer has a thermal conductivity of at least 5 W/m·K.
 27. The spacer ofclaim 22, wherein said first surface material forming said substantiallyplanar first surface of the spacer has a thermal conductivity of atleast 10 W/m·K, and wherein said second surface material forming saidsubstantially planar second surface of the spacer has a thermalconductivity of at least 10 W/m·K.
 28. The spacer of claim 23, whereinsaid spacer outer perimeter substantially defines a rectangle measuringabout 40 inches by about 48 inches.
 29. The spacer of claim 23, whereinsaid spacer outer perimeter substantially defines a rectangle measuringabout 42 inches by about 48 inches.
 30. The spacer of claim 23, whereinsaid spacer outer perimeter substantially defines a rectangle measuringabout 41 inches by about 48 inches.
 31. The spacer of claim 23, whereinsaid spacer defines a load capacity for the quantity of product of about1800 pounds.
 32. The spacer of claim 23, wherein said spacer defines aload capacity for the quantity of product of about 3600 pounds.
 33. Thespacer of claim 23, wherein said first surface includes a plurality ofperforations, said perforations are arranged such that at least one areaof continuous surface free of said perforations and sized to receive asuction gripping device is provided on said first surface, wherein saidat least one area of continuous surface free of said perforations andsized to receive a suction gripping device comprises an area of 4 sq.in.
 34. The spacer of claim 23, wherein said first surface and saidsecond surface are both formed of an aluminum material.
 35. The spacerof claim 23, wherein said first surface and said second surface are bothformed of a polymer.
 36. The spacer of claim 23, wherein said firstsurface comprises a first surface of a first 14 gauge aluminum plate andsaid second surface comprises a first surface of a second 14 gaugealuminum plate.
 37. The spacer of claim 18, wherein said first surfaceand said second surface are both formed of a 304 stainless steelmaterial.
 38. The spacer of claim 23, wherein said first surface andsaid second surface are both formed of a mild steel.
 39. The spacer ofclaim 23, wherein said supports are spaced from each by other by about4-6 inches measured along the y-axis of the Cartesian coordinate system,and wherein said supports extend along a trajectory defined by thez-axis to a height of about 0.25 to 3 in.
 40. The spacer of claim 23,wherein said spacer further comprises a lip extending from said spacerouter perimeter.
 41. A method of maintaining a quantity of a product ata desired temperature, comprising: preparing a pallet assembly bystacking a plurality of cases and a plurality of spacers on a pallet sothat the plurality of cases are separated from each other along a z-axisof a Cartesian coordinate system by the spacers, the spacers comprising:a substantially planar first surface extending in an x-y plane of theCartesian coordinate system, said planar first surface formed of a firstsurface material, said planar first surface defining a spacer outerperimeter of a size and shape about congruent to the outer perimeter ofthe pallet; a substantially planar second surface formed of a secondsurface material; and a plurality of supports extending between saidfirst surface and said second surface along a trajectory having adirectional component along a z-axis of the Cartesian coordinate system,whereby each of said plurality of supports space said first surface fromsaid second surface, said first surface, said second surface and saidsupports defining at least one airflow channel, each of said pluralityof airflow channels spanning a pair of opposing sides of at least one ofsaid plurality of spacers, wherein one of said pair of opposing sides ofsaid at least one spacer comprises an airflow inlet and the other ofsaid pair of opposing sides of said at least one spacer comprises anairflow outlet, whereby an airflow enters said at least one airflowchannel at said airflow inlet, traverses said channel and exits saidchannel at said airflow outlet to define an airflow trajectory from saidinlet to said outlet along an x-axis of the Cartesian coordinate system,whereby said support substantially precludes the airflow from exitingsaid channel along a trajectory defined by the y-axis of the Cartesiancoordinate system; directing a thermally conditioned airflow through theat least one airflow channel of the spacers to adjust the temperature ofthe product contained in the plurality of cases to the desiredtemperature.
 42. The method of claim 41, wherein said at least oneairflow channel comprises a plurality of airflow channels.
 43. Thespacer of claim 41, wherein said first surface and said second surfaceare both coated with polytetrafluorethylene.
 44. The method of claim 41,wherein said first surface material forming said substantially planarfirst surface of the spacers has a thermal conductivity of at least 3W/m·K, and wherein said second surface material forming saidsubstantially planar second surface of the spacers has a thermalconductivity of at least 3 W/m·K.
 45. The method of claim 41, whereinsaid first surface material forming said substantially planar firstsurface of the spacers has a thermal conductivity of at least 5 W/m·K,and wherein said second surface material forming said substantiallyplanar second surface of the spacers has a thermal conductivity of atleast 5 W/m·K.
 46. The method of claim 41, wherein said first surfacematerial forming said substantially planar first surface of the spacershas a thermal conductivity of at least 10 W/m·K, and wherein said secondsurface material forming said substantially planar second surface of thespacers has a thermal conductivity of at least 10 W/m·K.
 47. The methodof claim 41, wherein said step of preparing a pallet assembly comprisesthe step of preparing a plurality of pallet assemblies.
 48. The methodof claim 47, further comprising the steps of: positioning each of saidplurality of pallet assemblies on one of a plurality of racks in astorage warehouse space, each of the plurality of racks positionedadjacent to an aisle, whereby a forklift can access each of theplurality of pallet assemblies.
 49. The method of claim 47, wherein saidstep of directing a thermally conditioned airflow through the at leastone airflow channel of the spacers to adjust the temperature of theproduct contained in the plurality of cases positioned on either side ofthe plurality of spacers to the desired temperature comprises the stepsof: positioning each of the plurality of pallet assemblies in fluidcommunication with an air intake opening defined by one of a pluralityof racks occupying a storage warehouse space; actuating at least one fanin fluid communication with a airflow chamber, the airflow chamber influid communication with the air intake opening, whereby the step ofactuating the fan creates a circulation of ambient air flowing throughthe at least one airflow channel of each of the at least one spacer andthereafter to the air intake opening, and the airflow chamber and backto the warehouse space.
 50. The method of claim 41, wherein said spacerouter perimeter defines a rectangle measuring about 40 inches by about48 inches.
 51. The method of claim 41, wherein said spacer outerperimeter defines a rectangle measuring about 42 inches by about 48inches.
 52. The method of claim 41, wherein said spacer outer perimeterdefines a rectangle measuring about 41 inches by about 48 inches. 53.The method of claim 41, wherein said spacer defines a load capacity forthe quantity of product of about 1800 pounds.
 54. The method of claim41, wherein said spacer defines a load capacity for the quantity ofproduct of about 3600 pounds.
 55. The method of claim 41, wherein saidfirst surface includes a plurality of perforations, said perforationsare arranged such that at least one area of continuous surface free ofsaid perforations and sized to receive a suction gripping device isprovided on said first surface, wherein said at least one area ofcontinuous surface free of said perforations and sized to receive asuction gripping device comprises an area of 4 sq. in.
 56. The method ofclaim 41, wherein said first surface and said second surface are bothformed of a polymer.
 57. The method of claim 41, wherein said firstsurface and said second surface are both formed of an aluminum material.58. The method of claim 41, wherein said first surface comprises a firstsurface of a first 14 gauge aluminum plate and said second surfacecomprises a first surface of a second 14 gauge aluminum plate.
 59. Themethod of claim 41, wherein said first surface and said second surfaceare both formed of a 304 stainless steel material.
 60. The method ofclaim 41, wherein said first surface and said second surface are bothformed of a mild steel.
 61. The method of claim 41, wherein saidsupports are spaced from each by other by about 4-6 inches measuredalong the y-axis of the Cartesian coordinate system, and wherein saidsupports extend along a trajectory defined by the z-axis at a height ofabout 0.25 to 3 in.
 62. The method of claim 41, wherein said spacerfurther comprises a lip extending from said spacer outer perimeter.